JP2004208007A - Image-reading apparatus and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the SN ratio and shorten the reading time at the same time, with respect to an image reading apparatus for reading an image of a manuscript, and to provide a program for controlling the image reading apparatus by a computer. <P>SOLUTION: In an imaging apparatus, each line sensor made up of a plurality of pixels in a one-dimensional array is arranged at prescribed intervals, and different lines on the manuscript are read out by the line sensor with a prescribed amount of light exposure to generate image data. In a carrying means, at least one of the imaging means and the manuscript is moved crosswise to the line sensor so that a line to be read out by the line sensor is changed sequentially. In a processing means, the carrying means is controlled so that the same line on the manuscript becomes as an object to be read out by the line sensor, and the processing means adds each image data of the identical line generated individually by the line sensor by pixel units. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image reading device that reads an image of a document, and a program that controls a computer to control the image reading device.
[0002]
[Prior art]
2. Description of the Related Art Some image reading apparatuses realize image reading by capturing reflected light or transmitted light of a document using a line sensor (an imaging element in which a plurality of pixels are arranged one-dimensionally).
In recent years, in such an image reading apparatus, the pixel size has been reduced along with the increase in resolution.
[0003]
[Problems to be solved by the invention]
However, the reduction in the pixel size causes a decrease in sensitivity, and a high-speed reading deteriorates the S / N ratio. If the exposure time is lengthened to increase the S / N ratio, it takes a long time to read. Let it.
Therefore, an object of the present invention is to achieve both an improvement in the SN ratio and a reduction in the reading time when reading an image.
[0004]
[Means for Solving the Problems]
In the image reading device according to the first aspect, a plurality of line sensors each including a plurality of pixels arranged one-dimensionally are arranged at a predetermined interval, and a plurality of different lines on a document are simultaneously scanned by the line sensors at a predetermined exposure amount. Imaging means for reading and generating image data; moving means for moving at least one of the imaging means and the document in a direction orthogonal to the line sensor to sequentially change a line to be read by the line sensor; Controlling the means to read the same line on the document by the line sensor and adding image data of the same line individually generated by the line sensor in pixel units. Features.
[0005]
According to a second aspect of the present invention, in the image reading apparatus according to the first aspect, the processing unit determines an exposure amount at the time of reading by the line sensor according to a reading speed and an SN ratio. It is characterized by.
The image reading device according to claim 3, wherein the processing unit is configured to execute the preliminary reading of the document obtained as a result of preliminary reading performed by the imaging unit and the moving unit. The exposure amount at the time of reading by the line sensor is determined according to the luminance information.
[0006]
The image reading device according to claim 4, wherein in the image reading device according to claim 1, the processing unit controls at least one of the imaging unit and the document to the line sensor as a control mode for the moving unit. A first control mode in which the same line on the document is read by the line sensor at a constant pitch in a direction orthogonal to the document, and a predetermined number of movements with a short pitch and one movement with a long pitch. Providing two control modes, a second control mode to be repeatedly read by the line sensor without overlapping the lines on the original, and controlling the moving means by switching between the two control modes. It is characterized by.
[0007]
An image reading apparatus according to a fifth aspect is the image reading apparatus according to the fourth aspect, wherein the processing unit switches between the two control modes according to the type of the document.
The image reading device according to claim 6, wherein the processing unit is configured to execute the preliminary reading of the document obtained as a result of preliminary reading performed by the imaging unit and the moving unit. The above two control modes are switched according to luminance information.
[0008]
The program according to claim 7, wherein a plurality of line sensors each having a plurality of pixels arranged one-dimensionally are arranged at predetermined intervals, and the line sensors simultaneously read a plurality of different lines on the document with a predetermined exposure amount. An image reading apparatus comprising: an imaging unit that generates image data; and a moving unit that moves at least one of the imaging unit and the document in a direction orthogonal to the line sensor and sequentially changes a line to be read by the line sensor. A computer-implemented program for controlling a device, wherein the same line on the original is read by the line sensor by controlling the moving unit, and an image of the same line individually generated by the line sensor. A processing procedure for adding data in pixel units is provided.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
However, in the following, a description will be given using a film scanner that reads an image of a film document as an example of the image reading apparatus of the present invention. It is also assumed that the program of the present invention is recorded in a film scanner in an executable state in advance.
[0010]
FIG. 1 is a configuration diagram of the film scanner of the present embodiment.
1, a film scanner 10 includes a CPU 11, an illumination control unit 12, an optical block motor control unit 13, a sensor control unit 14, a signal processing circuit 15, an analog switch 16, an A / D converter 17, a memory 18, and an interface unit 19. Which are interconnected via a bus.
[0011]
The film scanner 10 includes an optical block motor 20 to which a control signal from the optical block motor control unit 13 is input, an optical block 21 connected to the optical block motor 20, and a transport path (not shown) for the film original 22. Etc. are provided.
The optical block 21 includes an illumination device 23 to which a control signal from the illumination control unit 12 is input, a lens 24, a three-line monochrome CCD 25 to which a control signal from the sensor control unit 14 is input, and the like. Here, the three-line monochrome CCD 25 includes three monochrome CCD line sensors arranged at predetermined intervals, and can output three systems of analog image signals at the same time.
[0012]
The output of the three-line monochrome CCD 25 is connected to the signal processing circuit 15, and the output of the signal processing circuit 15 is connected to the analog switch 16. From the analog switch 16, one system of analog image signal is output and connected to the A / D converter 17.
The interface unit 19 is connected to an external host computer 30. The host computer 30 is connected to a monitor 50 and an operation unit 70 such as a keyboard and a mouse.
[0013]
Here, the function of each part of the film scanner 10 will be described.
The illumination device 23 is controlled by the illumination control unit 12 that operates under the instruction of the CPU 11, and emits light of three colors of red light (R), green light (G), and blue light (B).
The lens 24 guides the transmitted light of the film original 22 obtained by the lighting of the light by the illumination device 23 to the three-line monochrome CCD 25 to form an image.
[0014]
In the 3-line monochrome CCD 25, each CCD line sensor is controlled by a sensor control unit 14 operating under the instruction of the CPU 11, performs photoelectric conversion by a light receiving unit of a plurality of pixels, and is guided by a lens 24. A signal charge corresponding to the transmitted light 22 is generated, and the signal charge is scanned to generate an analog image signal. That is, the three-line monochrome CCD 25 can simultaneously generate three systems of analog image signals corresponding to three different lines on the film document 22. Note that the three-line monochrome CCD 25 can generate an analog image signal using only one of the three CCD line sensors, and which of the three CCD line sensors is used depends on an instruction from the CPU 11. It is decided according to.
[0015]
The optical block motor 20 is controlled by the optical block motor control unit 13 that operates under the instruction of the CPU 11, and moves the optical block 21 by a predetermined distance in the sub-scanning direction. That is, the optical block 21 moves in the sub-scanning direction by the distance specified by the CPU 11.
In the present embodiment, the following two modes are prepared as a control method for moving the optical block 21.
[0016]
First, the first mode is a mode in which the optical block 21 is moved at a constant pitch.
For example, when the optical block 21 is moved at one line pitch, all the lines on the film original 22 are read by the CCD line sensors in the three-line monochrome CCD 25. Therefore, analog image signals are generated for all the lines by the three CCD line sensors.
[0017]
Hereinafter, a mode in which the optical block 21 is moved at a constant pitch is referred to as a “single step mode”.
In the single step mode, the pitch for moving the optical block 21 in the sub-scanning direction (hereinafter, referred to as “sub-scanning feed pitch”) is not limited to one line pitch, and a plurality of line pitches can be set. is there. However, in the present embodiment, it is assumed that the sub-scan feed pitch is set so that the same line on the film document 22 is read by each CCD line sensor in the three-line monochrome CCD 25. For example, when three monochrome CCD line sensors in the three-line monochrome CCD 25 are arranged at an interval of eight lines, a two-line pitch or a four-line pitch is set as the sub-scanning feed pitch.
[0018]
In the second mode, as described below, the optical block 21 is moved at a short pitch (hereinafter, referred to as “small step movement”) a predetermined number of times, and then the optical block 21 is moved at a long pitch (hereinafter, referred to as “small step movement”). , "Large step movement").
For example, if three monochrome CCD line sensors in the three-line monochrome CCD 25 are arranged at an interval of eight lines, and a small step movement is performed at one line pitch, the CCD line sensor located at the second position becomes the eighth CCD line sensor. In the small step movement, the movement reaches the line which has already been read by the first CCD line sensor. Similarly, the third CCD line sensor reaches the line which has already been read by the second CCD line sensor. Therefore, if the eighth small-step movement is not performed, but a large-step movement is performed to move 24 (8 × 3) lines at a time, the three CCD line sensors reach a line where no reading is performed.
[0019]
That is, by repeating seven small-step movements of one line pitch and one large-step movement of 24 lines, all lines on the film original 22 are replaced with any one of the three-line monochrome CCDs 25. The line sensor can read without duplication.
Hereinafter, a mode in which the small step movement and the large step movement are repeatedly performed is referred to as a “multi-step mode”.
[0020]
In the multi-step mode, the sub-scanning feed pitch at the time of small step movement is not limited to one line pitch, and a plurality of line pitches can be set. However, in the present embodiment, it is assumed that the sub-scanning feed pitch at the time of the small step movement is set so that lines at equal intervals on the film document 22 can be read. For example, as described above, when three monochrome CCD line sensors in the three-line monochrome CCD 25 are arranged at an interval of eight lines, the sub-scanning feed pitch at the time of small step movement is a two-line pitch, a four-line pitch, or the like. Is set.
[0021]
The signal processing circuit 15 performs a correlated double sampling process, a gain adjustment process, and the like on the analog image signal generated by the three-line monochrome CCD 25 in accordance with an instruction from the CPU 11.
The analog switch 16 converts the analog image signal subjected to various processes by the signal processing circuit 15 into a single-system analog signal in accordance with an instruction from the CPU 11 and supplies the analog signal to the A / D converter 17.
[0022]
The A / D converter 17 performs A / D conversion on one system of analog image signals supplied via the analog switch 16 to generate digital image data. Then, such image data is supplied to the memory 18 via the bus.
Note that if three A / D converters are provided without providing the analog switch 16, A / D conversion can be performed in parallel on three systems of analog image signals. However, A / D converters are expensive and their A / D conversion characteristics do not always match. Therefore, a configuration in which the analog switch 16 is provided and A / D conversion is performed by one A / D converter 17 as in the present embodiment is more preferable than a configuration in which three A / D converters are provided.
[0023]
The memory 18 stores image data supplied from the A / D converter 17 at the time of the main scan. Such image data is associated with a line address on the film original 22 by the CPU 11. Stored.
Therefore, when the main scan is performed in the single step mode as described above, three pieces of image data are stored in the memory 18 in association with the same line address. On the other hand, when the main scan is performed in the multi-step mode, one image data is stored in the memory 18 in association with each line address.
[0024]
Immediately after the start or immediately before the main scan, some CCD line sensors in the three-line monochrome CCD 25 may be out of the sub-scanning range on the film document 22. It is assumed that only image data within the scanning range is selected by the CPU 11 and stored in the memory 18.
The interface unit 19 supplies the image data stored in the memory 18 to the host computer 30 in accordance with the instruction of the CPU 11, and notifies the CPU 11 of the instruction from the host computer 30 to the film scanner 10.
[0025]
The host computer 30 displays image data supplied via the interface unit 19 and various operation screens on the monitor 50. Further, the host computer 30 notifies the CPU 11 in the film scanner 10 of the contents set by the operator via the operation unit 70 and an instruction to the film scanner 10 via the interface unit 19.
[0026]
The CPU 11 receives an instruction from the host computer 30 and controls the operation of each unit in the film scanner 10. Further, the image data obtained by the main scan in the single step mode is subjected to processing such as averaging and addition as described later.
[0027]
2 and 3 are operation flowcharts of the film scanner 10 of the present embodiment, and particularly show the operation of the CPU 11.
Hereinafter, an operation of the film scanner 10 of the present embodiment will be described with reference to FIGS.
First, when a pre-scan is instructed by the operator via the operation unit 70, the CPU 11 controls each unit in the film scanner 10 to perform a pre-scan (S1 in FIG. 2).
[0028]
That is, the CPU 11 instructs the illumination control unit 12 and the sensor control unit 14 to generate analog image data with an exposure amount for prescan using only one CCD line sensor, and controls the optical block motor control unit. By instructing the optical block 13 to move the optical block 21 at the sub-scanning feed pitch corresponding to the pre-scan resolution, the pre-scan is realized.
[0029]
Next, the CPU 11 obtains luminance distribution information of the image based on the image data obtained by the prescan, and determines whether the image of the film document 22 is darker than a predetermined state based on the luminance distribution information. A determination is made (S2 in FIG. 2).
When the image of the film original 22 is dark, the CPU 11 determines that the brightest point on the film original 22 becomes oversaturated during photoelectric conversion by the CCD line sensor in the three-line monochrome CCD 25 based on the image data obtained by the prescan. A maximum exposure amount (hereinafter, referred to as “saturated exposure amount”) is determined (S3 in FIG. 2).
[0030]
After that, when the resolution and the reading mode set by the operator via the operation unit 70 and the instruction to start the main scan are notified from the host computer 30 via the interface unit 19, the CPU 11 firstly performs the operation. The sub-scan feed pitch in the single step mode is determined according to the resolution set by the user (S4 in FIG. 2).
[0031]
However, in this embodiment, the sub-scanning feed pitch at which the same line on the film document 22 is read is determined by each CCD line sensor in the three-line monochrome CCD 25. That is, the resolution that can be set by the operator is a resolution finer than the interval between the CCD line sensors in the three-line monochrome CCD 25.
[0032]
In the present embodiment, it is assumed that the reading mode set by the operator is any one of the “high image quality mode”, the “standard mode”, and the “high speed mode”. That is, the operator sets the high image quality mode when giving priority to the improvement of the SN ratio over the reduction of the reading time, and sets the high speed mode when giving priority to the reduction of the reading time over the improvement of the SN ratio. If the settings are made and an intermediate effect between these modes is expected, the standard mode is set.
[0033]
The CPU 11 determines what mode the reading mode set by the operator is (S6 in FIG. 3).
When the high image quality mode is set, the CPU 11 sets the saturated exposure amount by the pre-scan as the exposure amount for the main scan (S7 in FIG. 3), controls each unit in the film scanner 10, and performs the single-step main scan. (S8 in FIG. 3).
[0034]
That is, the CPU 11 instructs the illumination control unit 12 and the sensor control unit 14 to generate analog image data with the exposure amount for the main scan using three CCD line sensors. In addition, the sub-scan feed pitch determined as described above is notified, and the instruction to move the optical block 21 in the single-step mode is issued, thereby realizing the single-step main scan.
[0035]
Then, the CPU 11 averages the image data obtained by such a single-step main scan in pixel units for each same line address (S9 in FIG. 3).
[0036]
When the standard mode is set, the CPU 11 sets an exposure amount of 1/3 of the saturated exposure amount as an exposure amount for the main scan (S10 in FIG. 3), controls each unit in the film scanner 10, and performs a single step. (S11 in FIG. 3).
Then, the CPU 11 adds, on a pixel-by-pixel basis, image data obtained by such a single-step main scan (S12 in FIG. 3).
[0037]
Further, when the high-speed mode is set, the CPU 11 sets the exposure amount of 1/6 of the saturated exposure amount as the exposure amount for the main scan (S13 in FIG. 3), and controls each unit in the film scanner 10 to double the exposure amount. The main scan is performed in a single step with the gain adjustment (S14 in FIG. 3).
That is, the CPU 11 instructs the signal processing circuit 15 to perform double gain adjustment in addition to the instructions to the illumination control unit 12, the optical block motor control unit 13, and the sensor control unit 14 as described above. This realizes a single-step main scan.
[0038]
Then, the CPU 11 adds, on a pixel-by-pixel basis, image data obtained by such a single-step main scan (S15 in FIG. 3).
On the other hand, when the image of the film original 22 is bright (NO side in FIG. 2S2), or the CPU 11 determines the sub-scanning feed pitch during small-step movement in the multi-step mode according to the resolution set by the operator ( (FIG. 2S16).
[0039]
However, in the present embodiment, the sub-scanning feed pitch is determined by each CCD line sensor in the three-line monochrome CCD 25 such that equally spaced lines on the film document 22 are read without overlapping. That is, the resolution that can be set by the operator is a resolution finer than the interval between the CCD line sensors in the three-line monochrome CCD 25.
[0040]
Then, each section in the film scanner 10 is controlled to perform a main scan by multi-step (S17 in FIG. 2). That is, the CPU 11 instructs the illumination control unit 12 and the sensor control unit 14 to generate analog image data with the exposure amount for the main scan using three CCD line sensors. In response to this, the sub-scanning feed pitch at the time of the small-step movement determined as described above is notified, and the instruction to move the optical block 21 in the multi-step mode is performed, thereby realizing the multi-step main scan.
[0041]
As described above, in the present embodiment, in the main scan in the single step mode, if the high image quality mode is set, image data obtained by three exposures with the saturated exposure amount is averaged. . Therefore, the effect of improving the S / N ratio can be obtained as in the case of the existing multi-sample scan. The three exposures with the saturated exposure amount are performed simultaneously with the exposure for the other lines. Therefore, unlike the existing multi-sample scan in which the reading time becomes longer with an increase in the number of exposures, reading by three exposures can be realized with the same reading time as reading by one exposure. .
[0042]
In the present embodiment, the three-line monochrome CCD 25 is provided. However, instead of the three-line monochrome CCD 25, N (N ≧ 2) monochrome CCD line sensors are arranged at predetermined intervals. When a monochrome CCD is provided, reading by N exposures can be realized in a reading time approximately equal to reading by one exposure.
[0043]
In other words, according to the high image quality mode of the present embodiment, the SN ratio is remarkably increased while the reading time is almost the same as when reading is performed by one exposure with the saturated exposure amount using a single CCD line sensor. Can be improved.
In addition, during the main scan in the single step mode, if the standard mode is set, image data obtained by three exposures with an exposure amount of 1/3 of the saturation exposure amount is added. Therefore, the reading time can be reduced to about 1/3 while realizing the same SN ratio as in the case of performing reading with one exposure with the saturated exposure amount using a single CCD line sensor.
[0044]
In the present embodiment, the three-line monochrome CCD 25 is provided. However, when the above-described N-line monochrome CCD is provided instead of the three-line monochrome CCD 25, the same line on the film document 22 is used N times. Can be realized by exposure. Therefore, in such a case, if image data obtained by N exposures with an exposure amount of 1 / N of the saturation exposure amount are added, one exposure with the saturation exposure amount can be performed using a single CCD line sensor. The reading time can be reduced to about 1 / N while realizing the same SN ratio as in the case of performing reading.
[0045]
Further, when the high-speed mode is set during the main scan in the single-step mode, the gain of the analog image signal obtained by three exposures with an exposure amount of 1/6 of the saturation exposure amount is doubled. , And the resulting image data is added. Therefore, the reading time can be significantly reduced while suppressing the deterioration of the SN ratio.
[0046]
In this embodiment, when the high-speed mode is set, the exposure amount is set to 1/6 of the saturation exposure amount and the gain is doubled. However, if the exposure amount is reduced and the gain adjustment amount is increased, the gain amount is increased. The reading time can be further reduced.
If an N-line monochrome CCD in which N (N ≧ 2) monochrome CCD line sensors are arranged at predetermined intervals is provided instead of the 3-line monochrome CCD 25, the same line on the film document 22 is provided. Reading by N exposures can be realized. Therefore, if the gain of an analog image signal obtained by N exposures with an exposure amount of 1 / N · M of the saturated exposure amount is adjusted by a factor of M, the reading time can be reduced by about 1 / N · M while suppressing the deterioration of the SN ratio. M. Further, the image data finally obtained may be multiplied by M without adjusting the gain of the analog image signal by M times.
[0047]
By the way, in the main scan in the multi-step mode, unlike the main scan in the single step mode as described above, image data can be obtained by one exposure using any one of the CCD line sensors in the three-line monochrome CCD 25. Become. Therefore, the reading time can be greatly reduced as compared with the main scan in the single-step mode. However, when the output characteristics of the three CCD line sensors in the three-line monochrome CCD 25 vary, the image data of the flat part is reduced. Noise may occur. Note that such noise is hardly noticeable in a bright image, and is easy to notice in a dark image.
[0048]
In the present embodiment, the main scan in the single step mode and the main scan in the multi-step mode can be switched according to the type of the film original 22 and the brightness of the image on the film original 22. Scanning is performed only at the time of reading a bright image in which noise is not conspicuous as in the case where the image of the film document 22 is bright.
[0049]
That is, according to the present embodiment, a bright image in which noise is less noticeable as described above can be read at high speed without deteriorating the SN ratio.
In the present embodiment, the main scan in the single step mode is performed according to the reading mode set by the operator, but the reading mode is set by the CPU 11 according to the brightness state of the image of the film document 22. You may.
[0050]
For example, the CPU 11 obtains luminance distribution information of the image based on the image data obtained by the prescan, and uses such luminance distribution information to change the brightness of the image of the film document 22 to “dark”, “standard”, It is classified into three stages of “bright”. When the image of the film original 22 is dark, the high image quality mode is set. When the brightness of the image of the film original 22 is standard, the standard mode is set. When the image of the film original 22 is bright, the mode is set. Just set the high-speed mode.
[0051]
Further, in the present embodiment, the resolution that can be set by the operator is smaller than the interval between the CCD line sensors in the three-line monochrome CCD 25, but another resolution may be set.
However, when the resolution is set to be coarser than the interval between the CCD line sensors in the 3-line monochrome CCD 25, the same line on the film original 22 is read by three CCD line sensors, Is difficult to read without duplication. Therefore, the main scan is performed using the first and third CCD line sensors among the three CCD line sensors, or the main scan is performed using only one of the CCD line sensors. Need to do.
[0052]
Further, in the present embodiment, the image data obtained by the main scan in the single-step mode is averaged or added for each same line address. The processing may be performed when one set of image data is prepared, or may be performed after three sets of image data are prepared for all lines to be read. Instead of mere averaging or addition, weighted averaging or weighted addition may be performed according to the output characteristics of each CCD line sensor in the three-line monochrome CCD 25.
[0053]
In the present embodiment, the position of the object to be read on the film document 22 is changed by moving the optical block 21 in the sub-scanning direction. However, if the main scan in the single-step mode or the multi-step mode can be realized, A configuration in which the film original 22 is moved may be used.
Further, in the present embodiment, the determination of the sub-scanning feed pitch and the exposure amount for the main scan, and the averaging and addition of the image data obtained by the main scan in a single step are performed by the CPU 11. You may go.
[0054]
【The invention's effect】
As described above, according to the present invention, it is possible to achieve both an improvement in the SN ratio and a reduction in the reading time.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a film scanner.
FIG. 2 is an operation flowchart of the film scanner.
FIG. 3 is an operation flowchart of the film scanner.
[Explanation of symbols]
10 Film scanner
11 CPU
12 Lighting control unit
13 Optical block motor controller
14 Sensor control unit
15 Signal processing circuit
16 Analog switch
17 A / D converter
18 memory
19 Interface section
20 Optical block motor
21 Optical block
22 Film manuscript
23 Lighting equipment
24 lenses
25 3-line monochrome CCD
30 Host computer
20 monitors
71 Operation unit

Claims (7)

A plurality of line sensors in which a plurality of pixels are arranged one-dimensionally are arranged at a plurality of predetermined intervals, and an image pickup means for generating image data by simultaneously reading a plurality of different lines on the document with a predetermined amount of exposure by the line sensors;
Moving means for moving at least one of the image pickup means and the document in a direction orthogonal to the line sensor, and sequentially changing a line to be read by the line sensor;
Processing means for controlling the moving means so that the same line on the original is read by the line sensor, and adding image data of the same line individually generated by the line sensor in pixel units. An image reading apparatus, comprising: The image reading device according to claim 1,
The processing means includes:
An image reading apparatus, wherein an exposure amount at the time of reading by the line sensor is determined according to a reading speed and an SN ratio. The image reading device according to claim 1,
The processing means includes:
An image reading apparatus, wherein an exposure amount at the time of reading by the line sensor is determined according to luminance information of the document obtained as a result of preliminary reading performed by the imaging unit and the moving unit. The image reading device according to claim 1,
The processing means includes:
As a control mode for the moving unit, at least one of the imaging unit and the document is moved at a constant pitch in a direction orthogonal to the line sensor, and the same line on the document is set as a reading target of the line sensor. A second control mode in which a line on the document is read by the line sensor without overlapping lines on the document by repeatedly performing a predetermined number of movements at a short pitch and a single movement at a long pitch. An image reading apparatus comprising the following two control modes, wherein the two control modes are switched to control the moving unit. The image reading device according to claim 4,
The processing means includes:
An image reading apparatus, wherein the two control modes are switched according to the type of the document. The image reading device according to claim 4,
The processing means includes:
The image reading apparatus according to claim 1, wherein the two control modes are switched according to luminance information of the document obtained as a result of preliminary reading performed by the imaging unit and the moving unit. A plurality of line sensors in which a plurality of pixels are arranged one-dimensionally are arranged at a plurality of predetermined intervals, and an image pickup means for generating image data by simultaneously reading a plurality of different lines on the document with a predetermined amount of exposure by the line sensors; A computer-readable storage medium storing at least one of the image pickup unit and the document in a direction orthogonal to the line sensor and sequentially changing a line to be read by the line sensor. And
Controlling the moving means so that the same line on the original is read by the line sensor, and a processing procedure is provided in which image data of the same line individually generated by the line sensor are added in pixel units. Program characterized by the following.

Images